Rivet analyses referenceSND_2015_I1389908Cross section for $e^+e^-\to \pi^+\pi^-\pi^0$ between 1.05 and 2 GeV.Experiment: SND (VEPP-2M) Inspire ID: 1389908 Status: VALIDATED Authors:
Beam energies: (0.5, 0.5); (0.5, 0.5); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0) GeV Run details:
Measurement of the cross section for $e^+e^-\to \pi^+\pi^-\pi^0$ by SND for energies between 1.05 and 2 GeV. Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples. Source code: SND_2015_I1389908.cc 1// -*- C++ -*-
2#include "Rivet/Analysis.hh"
3#include "Rivet/Projections/FinalState.hh"
4
5namespace Rivet {
6
7
8 /// @brief e+ e- > pi+ pi- pi0
9 class SND_2015_I1389908 : public Analysis {
10 public:
11
12 /// Constructor
13 RIVET_DEFAULT_ANALYSIS_CTOR(SND_2015_I1389908);
14
15
16 /// @name Analysis methods
17 /// @{
18
19 /// Book histograms and initialise projections before the run
20 void init() {
21 // Initialise and register projections
22 declare(FinalState(), "FS");
23 book(_num3pi, 1,1,1);
24 for (const string& en : _num3pi.binning().edges<0>()) {
25 double end = std::stod(en)*GeV;
26 if(isCompatibleWithSqrtS(end)) {
27 _ecms = en;
28 break;
29 }
30 }
31 if(_ecms.empty()) MSG_ERROR("Beam energy incompatible with analysis.");
32 }
33
34
35 /// Perform the per-event analysis
36 void analyze(const Event& event) {
37 const FinalState& fs = apply<FinalState>(event, "FS");
38
39 map<long,int> nCount;
40 int ntotal(0);
41 for (const Particle& p : fs.particles()) {
42 nCount[p.pid()] += 1;
43 ++ntotal;
44 }
45 if(ntotal!=3) vetoEvent;
46 if(nCount[-211]==1&&nCount[211]==1&&nCount[111]==1)
47 _num3pi->fill(_ecms);
48 }
49
50
51 /// Normalise histograms etc., after the run
52 void finalize() {
53 scale(_num3pi, crossSection()/ sumOfWeights() /nanobarn);
54 }
55
56 /// @}
57
58
59 /// @name Histograms
60 /// @{
61 BinnedHistoPtr<string> _num3pi;
62 string _ecms;
63 /// @}
64
65
66 };
67
68
69 RIVET_DECLARE_PLUGIN(SND_2015_I1389908);
70
71
72}
|